How High-Fat Diets Promote Colon Cancer Growth Has Been Discovered

While cancer deaths have declined, colorectal cancer incidence has risen in people under 55. According to American Cancer Society data, between 2007 and 2016, deaths in this younger group increased by 1 percent. The relationship between colorectal cancer and high-fat diets has long been studied. In February 2019, Cell published a study discovering that high-fat diets (HFDs) disrupt the balance of intestinal bile acids, triggering hormonal signals that lead to cancer. This may explain why colorectal cancer, which develops over decades, is more common in young people eating high-fat diets.

Research at the Salk Institute in the United States used cancer mouse models with mutations in the APC gene. APC gene mutation is the most common mutation seen in people with colorectal cancer.

According to the research results, cancer developed faster in mice fed high-fat diets.

Our intestines are among the body’s most active organs. As we eat, the damaged layer lining their interior is constantly renewed. This renewal is provided by stem cells in the intestinal lining. Colon and rectal cancers result from accumulated mutations in these stem cells. The most common colorectal-related mutation occurs in the APC gene. APC generally acts as a tumor suppressor gene . APC mutations cause uncontrolled cell division.

- Related topic: What You Need to Know About Colon and Rectal Cancer

The study discovered that bile acids send hormonal signals to intestinal stem cells through the Farnesoid X receptor (FXR) . High-fat diets increase two specific bile acids, disrupting FXR receptor activity. Normally, FXR ensures safe, slow renewal of the intestinal lining. When bile acids block it, stem cells proliferate rapidly and DNA damage accumulates.

Benign (non-cancerous) tumors were also seen in mice with APC mutations. In humans, adenomas with a polyp structure are common in the intestines and are removed during colonoscopies . Such growths take decades to become cancerous. In mice with APC mutations, adenomas rapidly begin becoming cancerous when high-fat diets (HFDs) are given.

Researchers also tested a new cancer drug. FexD activates FXR in intestinal stem cells (agonist). FExD successfully repaired damage caused by imbalanced bile acids in mouse organ models and human colorectal cancer cell lines. The study’s graphical summary is below:

FExD can be used after its effectiveness is demonstrated in clinical trials. It readily reaches the large intestine and acts directly on FXR receptors, causing fewer adverse effects.

What does this study mean for us?

• This study, by reducing inflammation , may contribute to developing treatment strategies aimed at restoring intestinal health and halting tumor progression.
• In hereditary colorectal syndromes , adding high-fat diets further increases cancer risk.
• Increased bile acids have been associated with colorectal cancer development. High-fat diets increase bile acid secretion.
• Diet is highly important in cancer prevention. Research shows that low-fat diets protect against many cancer types. Remember: you may carry inherited cancer-related genes, but a balanced, healthy diet can reduce your cancer risk. 

RELATED TOPICS:

- Which Foods Reduce Colon Cancer Risk and Increase Recurrence Risk?

- Post-Treatment Breast Cancer Recurrence Linked to Fat Metabolism